1. Field of the Invention
The invention relates to a system and method that provides the capability to a valve lifter of a piston internal combustion engine (I.C.E.) to act in a variable way on the respective valve, as well as the variation of its timing in general, namely the variation of the valve opening time moment, as well as the variation of the valve opening-valve closing time duration. This variation is executed gradually. With reference to similar valves of the same internal combustion engine cylinder, the gradual variation of the characteristics of one valve to follow at a predetermined time lapse the gradual variation of the characteristics of another valve with the purpose of improving the internal combustion engine performance in the medium and lower operation RPM range.
2. Brief Description of the Background of the Invention Including Prior Art
It is well known that a conventional, presently in use valve lifter, mechanically or hydraulically adjusted, is constantly in contact with the respective cam of a rotating camshaft of an internal combustion engine, and transmits the motion for the opening or closing of the respective valve in a stable manner, with the help of the valve spring.
A further control of the valve motion is achieved according to U.S. Pat. No. 4,765,268 and U.S. Pat. No. 4,689,084 through a valve mechanism, which have the basic idea of controlling the pressure of a hydraulic means securely with the respective valve, wherein the hydraulic means is able to penetrate and come out of a chamber, which chamber is disposed between the respective cam of the internal combustion engine cam-shaft and the upper end of a movable small piston.
The known system requires an electromagnetic valve through which the control of the hydraulic means is achieved and a reservoir for the returning hydraulic means. This reservoir is located outside the electromagnetic valve or is part of the electromagnetic valve construction. A consequence of the above mentioned mechanism is the possibility of changing the operational characteristics of an internal combustion engine valve.
In spite of that, the above mentioned mechanism, has the disadvantage of requiring increased space between the valve end of the respective internal combustion engine cylinder and the corresponding cam, resulting in the need for a new cylinder head design and the increase in production cost.
Another disadvantage is also the fact that the complicated mechanism in conjunction with the mass of its components is creating obviously inertia problems during the engine operation. Finally, the manufacturing cost of the mechanism multiplied by the number of the valves is considerably increasing the production cost of a motor.